Sequential access storage devices are used to provide persistent storage of data. An example of such a device is a tape drive. The media used in a tape drive is a strip of magnetically sensitive material in the form of a tape. The tape is passed over a read/write head of the tape drive which then interacts with the magnetically sensitive material to read/write data. Data is read/written to the portion of the tape that is currently in contact with the read/write head as the tape is moved over the read/write head. In order to access data on a different portion of the tape, the tape must be rewound or forwarded to the desired position. A tape drive is a sequential access storage device because the read/write head cannot be moved to the desired position without traversing the portions of the tape between the current and desired position.
A sequential access storage device may be connected to a computer through a network. For example, in a Storage Area Network (SAN) or Network Associated Storage (NAS) system, a sequential access storage device may be connected to a network. Some typical networks used in SAN and NAS systems include Fiber Channel or Internet Protocol networks. The computer may also be connected to the network. When the computer needs to access the sequential access storage device to read or write data, the computer communicates with the sequential access storage device over the network.